# as -arch i386 boot_att.s -o boot.bin
# dd if=/dev/zero of=boot.img bs=512 count=2880
# dd if=boot.bin of=boot.img bs=512 count=1
# dd if=/dev/zero of=boot.img skip=1 seek=1 bs=512 count=2879
.code16
.text
start:
  mov %cs, %ax
  mov %ax, %ds
  mov %ax, %es
  # movb %ah, boot_msg+17  # tweet

  mov $boot_msg, %ax
  # add $0x7c00, %ax

  mov %ax, %bp  # point to the message
  mov $0x10, %cx  # number of characters do display
  mov $0, %dx  # display on row 1 column 1
  # mov $0x1004, %dx  # display on row 17 (=0x10+1), column 5 (=0x04+1)
  mov $0x000c, %bx  # display in red
  mov $0x1301, %ax  # int 10, function 0x13, sub-function 01
  int $0x10
loop0:
  jmp loop0
boot_msg:
.ascii "Loading system ..."
.byte 65,66,67,68,69,70
.byte 13,10  # carriage return and newline
.org 510
.word 0xaa55
